Brian Steinberg Senior TV EditorAndrew Ross Sorkin, the New York Times journalist and CNBC morning host, will take on a new assignment for NBC News: gaining an edge in the TV-news industry’s expanding streaming wars.Sorkin will host and produce a limited-run original series for NBC News Now, the NBC News streaming service that its parent has promoted aggressively in recent weeks as rival CNN prepares to launch a new streaming venture called CNN Plus. Sorkin’s streaming debut is expected to examine “the people, trends, institutions and forces shaping our world,” according to an NBC News statement.